What exactly is the whole "I have nothing to say to you O'Brien" thing about? So far as we know Riker and O'Brien were on excellent terms when they parted. Okay it gets rid of the Chief quickly, but it's a hell of a chance to take - what if he'd said "no sir, I haven't a clue why. What's the problem?" Surely Riker would have done better to chat for a minute or two, then shoot a few meaningful glances at Kira behind her back. That would get rid of the Chief pretty fast, I would think.

In fact, I find the whole reaction to Riker a little curious. Everyone seems to act as if he's an old friend of theirs that they've known for years - even Kira reacts that way. But so far as we know only Dax has ever even met him before - and that happened offscreen.

Great Moment :

Defiant strutting her stuff!

Factoid :

This is the first episode to feature quantum torpedoes.

The producers had considered bringing Thomas Riker onto the show a couple of times. One concept had been that that Maquis had suddenly become a much larger threat, which turned out to be because Thomas had become their leader.

The episode is based in part on the Sidney Lumet book "Fail Safe", in which the US President must help the Russians to shoot down an American bomber which is mistakenly trying to bomb Moscow.

Guest stars Shannon Cochran and Michael Canavan met for the first time on the set of this episode; they would subsequently marry.

Jonathan Frakes always hoped that Thomas Riker would return to Deep Space Nine, noting that since Kira had promised to rescue him there was a good excuse to bring him back. The producers, however, would subsequently inform writers that no ideas for another Thomas Riker story would be welcome.

This episode establishes that Sisko helped to design the Defiant, and was in command of the shipyard where it was built.

According to the novel "Quarantine", Voyager's Chakotay was the Maquis leader who came up with the plan for Thomas Riker to steal the Defiant.

Plotline

Thomas Riker returns, posing as Will Riker in order to steal the USS Defiant from DS9. Now a Maquis operative, Thomas is determined to use the warship to penetrate Cardassian space and investigate the mysterious Orias system. Sisko must go against years of training in order to help the Cardassians hunt down the ship and destroy it.

Analysis

Okay, here's a thought. Remember back in TOS, "The Enemy Within"? A transporter splits Kirk into two different versions of himself, one who is basically good, but passive, and the other evil, but aggressive? Well, in "Second Chances" we find that some years before Will Riker went through a difficult transport and this has resulted in a duplicate. But... what if it wasn't a duplicate so much as another mirroring? Not to the same extent as happened with Kirk, obviously. But what if the planet's atmosphere storm thingies did something similar to the weird rocks in Enemy Within? What if the Riker who beamed up came out just a little bit "good", and the one who remained below came out just a little bit "evil"

And look at this episode... when Thomas turns up, he has a duplicate beard just like real Riker. But when he stuns Kira and steals the Defiant, he removes the sides, to make it... a goatee!!!! And, as the TOS episode "Mirror Mirror" teaches us, the goatee is the sign of evil!

There's no doubt in my mind. Thomas is the evil transporter twin of the good Riker.